As mobile computing devices become more integrated and include more computing power, they may generate more heat. For example, a modern smartphone may include one or more highly integrated components known as a system on a chip (“SoC”) or a system in package (“SiP”). Each SoC or SiP may have one or more integrated circuits (“ICs”) with one or more processor cores, memory circuits, graphics processing circuits, radio frequency communication circuits, and other digital and analog circuits. Further, multiple SoCs or SiPs may be stacked in a package on package (“PoP”) configuration. A common PoP configuration includes one SoC or SiP package that has processing and other circuits, with a second stacked package that includes volatile and/or non-volatile memory components.
These highly integrated processing components may generate a large amount of heat within a tightly integrated packaging structure. Additionally, many manufacturers desire to increase the number of processing cores and processor clock speeds, further increasing the amount of heat generated in the package. For mobile computing device processors especially, heat may become a limiting factor to computing performance.
Typically, mobile computing devices may include passive heat dissipation components (e.g., heat sinks, etc.) that transfer heat from the processor package and/or other components that require heat dissipation to an exterior surface of the mobile computing device. However, the overall ability to dissipate heat from the mobile computing device may be limited by the thermal conduction paths between the exterior surfaces of the mobile computing device and the environment (e.g., air or other medium in contact with the exterior surface). As power consumption of mobile processors continues to increase, passive heat dissipation techniques may no longer be able to keep up with the heat generated by the mobile computing device. While there are known techniques for active cooling such as cooling fans, these techniques may be difficult to integrate into the limited enclosure space of mobile computing devices.